Microstructure and mechanical properties of Nd:YAG laser welded Invar 36 alloy

Invar 36 alloy is increasingly used as a structural material for manufacture of liquefied natural gas (LNG) transporters and storage tanks. However, the conventional arc welding of Invar 36 alloy has high susceptibility of hot-cracking. As a high-energy-beam welding process, laser welding could be effective for producing defect-free Invar 36 weld. In the present study, defect-free Invar 36 weld was successfully produced by Nd:YAG laser welding. The microstructure and mechanical properties of weld were also tested.